Lock for a quick opening cover of a pressure-resistant shell



United States Patent Alexandr Pavlovich Poltorak,

ul. Schorsa, 18-a kv. 60, Donetsk, U.S.S.R. 744,530

July 12, 1968 Nov. 10, 1970 Inventor Appl. No. Filed Patented LOCK FOR AQUICK OPENING COVER OF A PRESSURE-RESISTANT SHELL 1 Claim, 9 DrawingFigs.

US. Cl. 292/49, 292/197, 292/304 Int. Cl. E05c 3/16, E05c 9/00 Field ofSearch 292/44, 45, 46, 47, 49,11, 51,197, 37, 256.5, 256.6, 256.65, 257,256.69, 304, (T)

[56] References Cited UNITED STATES PATENTS 1,160,814 11/1915 Allen292/44 1,199,857 10/1916 Zinn 292/13 1,684,983 9/1928 Clark 292/3042,344,300 3/1944 Hagenbook 198/220 3,235,124 2/l966 Kuerer 220/553Primary Examiner- Richard E. Moore Assistant Examiner-Robert L. WolfeAttorney-Waters, Roditi, Schwartz & Nissen ABSTRACT: Apressure-resistant shell has an openable cover on a housing secured by alock. The lock has clips constituted as pivotal levers mounted on theshell, and mating edges of the cover and housing are embraced by shelveson the levers bounding grooves in which the mating edges are receivedwhen the levers are moved in common by a drive therefor.

Patented Nov, 10, 1970 Sheet 2 013 Patented Nov. 10, 1970 Sheet r ll 'opened covers in the above-mentioned shells incorporating clips turnableby a common drive and made as flat levers mountable on the cover byaxles extending perpendicular to the plane of a window in the shellhousing closed by the cover.

When the levers turn about their axles, their edges ente housinggrooves, insuring the closing of the shell.

In the locks of the known designs, the flat levers are rigidly mountedon their axles of rotation. When employing the shells with such locks,the pressure developing inside the shell acts on the axles of rotationof these levers, which results in elastic and residual deformation ofsaid axles and, correspondingly, in the production of a greater gapbetween the meeting edges of the cover and the shell housing.

Furthermore, the cover and the housing have a common lack at flatness ofthe meeting edges, and, since the flat levers are rigidly secured ontheir axles, they are capable of overcoming this lack of flatness, whichleads to a considerable wear of the meeting surfaces ofthe levers andthe cover edges, as well as of the housing, and, consequently, to theproduction ofgreater gaps between them.

It is an object of the present invention to provide a lock for aquick-opened cover insuring easy and quick opening and closing of theshell, a sealing gasket being provided between the cover and thehousing. I

An important object of the invention is to provide a lock for aquick-opened cover, insuring better explosion protection of the shell,reliability in operation and longer service life.

Still another object of the invention is to provide a lock for aquick-opened cover, insuring easy repair.

These and other objects of the invention are achieved by providing alock for a quick-opened cover of the above-mentioned shells wherein,according to the invention, each of the levers has at one end thereof agroove adapted for accommodating meeting edges of the cover and thehousing, which groove forms shelves embracing said edges when the leversturn about their axles of rotation.

The invention will become more apparent from the description of anexemplary embodiment thereof, reference being had to the accompanyingdrawings, wherein:

FIG. 1 is a front view of the lock, the shell cover being opened;

FIG. 2 is a rear view of the same look without the housing bottom, theshell cover being closed;

FIG. 3 is a perspective view ofa turnable lever of the lock of theinvention;

FIG. 4 is a section taken on line lV-IV in FIG. 2;

FIG. Sis a section taken on line V-V in FIG. 2;

FIG. 6 is a front view ofthe lock, in a second version;

FIG. 7 is a section taken on line VII-VII in FIG. 6;

FIG. 8 is a front view of the lock in closed position, according to athird version; and

FIG. 9 shows the lock of FIG. 8 in open position.

The lock of a quick-opened cover in explosion-proof andpressure-resistant shells comprises turnable clips made as double-armlevers 1 (FIGSv l and 2) mounted on a cover 2 by means of axles 3. Theshell is understood to comprise the conjugated cover 2 and housing 9.

Each of the double-arm levers 1 (FIG. 3) has a groove 4 at one end, saidgroove forming shelves 5 and 6 embracing, during the turn of the leversI about the axles 3 (FIG. I), the meeting edges 7 and 8 of the cover 2and a housing 9, respectively. The lower shelves 6 of the levers ll(FIG. 4) are in constant engagement with the edge of the cover 2 and arearranged between said edge and projections Ill rigidly secured in thecover 2. The axles 3 are screwed into the projections 10.

The height of the lower shelf6 is somewhat less than that of the grooveformed by the edge 7 and the projection 10, which permits the levers todisplace about the respective axles 3 in the course of the shell openingand closing.

The upper shelves 5 (FIG. 5 embrace,during the turning of the levers l,the edge 8 of the housing 9, as the lock becomes closed, and releasedsaid edge as the lock is opened.

The height of the groove 4 in the levers 1 is more than the totalthickness of the edges 7 and 8 of the cover 2 and the housing 9 of theshell by a predetermined magnitude.

The other end of each of the levers 1 includes a portion which forms anangle of about with the rest of the lever.

The levers 1 turn about their axles 3 under the action of rolls 11 whoseaxles 12 (FIG. 5) are rigidly mounted on a turnable ring 1.3.

The ring 13 turns about the central axis of the cover 2 by aneccentrically arranged disk 14 (FIG. I) cooperating with plates 15rigidly fixed on the ring 13. The provision of the eccentricallyarranged disk ensures a rapid opening of the cover The ring 13 freelyturns within a recess provided in the projections 10 (FIG. 4) and isprevented, in any position, from falling out of the cover 2 by theturnable levers I. The disk 14 is actuated from the outside by a controlhandle 16.

The lock operates in the following manner.

As the shell is closed, the control handle 16 is turned through an angleof the disk 14 turns the ring 13 about the central axis of the cover 2,while the rolls 11 (FIG. I) run on the ends of the levers l and turnthem about the axles 3. As a result, the meeting edges 7 and 8 of thecover 2 and the housing 9 are embraced by the shelves 5 and 6 of thelevers 1, to form a tight connection of the cover 2 with the housing 9.

In another embodiment of the invention, the axles of rotation of theturnable levers are secured to the shell housing, which helps reduce theweight of the cover and permits the use of the locks of very large sizesin the shells.

In this case, levers 17 (FIGS. 6 and 7) have axles 18 of rotationsecured in the shell housing 19. The levers 17 are similar to thosedescribed hereinabove.

The levers 17 are turnable about the axles 18 by means of a turnablering 21 made up of disks 22 interconnected by rollers 23. One of thedisks 22 acts on an arm 17 of the lever 17. The ring 21 is turned, forinstance, by a worm drive not shown in the drawing.

In this version, the lock functions analogously.

The present lock may also be utilized in shells with rectangular covers.FIGS. 8 and 9 show a third embodiment of the lock of the invention, fora rectangular cover. In this version, the clips are made as single-armlevers 24 secured on a cover 25 by axles 26.

Serving as the drive for the levers 24 is a moving plate 27 connected tothe levers by means of hinged links 28.

The plate 27 is actuated eccentrically by a disk 29 controlled fromoutside. The operation of the lock in this version is similar to thatdescribed hereinabove.

As is clear from the examples, the present lock is adapted to be usedwith the cover of any shape, the levers being arranged outside or insidethe shell.

The fixation of the levers on the axles may be on the cover or thehousing of the shell, the axles being arranged together with the leversor independently.

The turnable levers may be fashioned as single-arm or double-arm levers.Sometimes, especially in rectangular covers, the levers may be bothsingle-arm and double-armed at the same time.

The levers may be actuated either through the interaction of theirsurfaces directly with a moving element of the drive or throughcooperation with it via intermediate links.

The moving element of the drive can be fashioned as a plate, frame,disk, ring, nut or a combination of these.

The moving element of the drive can be actuated from the outside ofinside of the shell by a manually operated drive (pinion, eccentricdisk, hoisting jack, etc.) or by an automatic drive (hydraulic,pneumatic, electromagnetic one, etc.)-.

Thus, the exemplary embodiments of the locks described hereinabovepermit to insure small gaps between the meeting edges of the cover andthe housing of the shell (within 0.05- 0.1 mm.), which makes the lockspractical in explosionproof shells designed for operation in explosivepremises and in outdoor installations of all classes, categories andgroups of flammability.

Additionally, in the above-considered types of locks, the insidepressure caused by an explosion in the shell is resisted by the shelvesof the levers, which should therefore be made from quality steel with amargin of safety. The edges of the cover and the housing are subjectedto shear loads and bend via a shelf with closed perimeter, which makesthem stable to any pressures practically developing inside the shell.The axles of rotation of the levers are free from the effect of theexplosioncaused pressure.

Practically, the present lock may be made to withstand any pressure.

Since the lock is motionless in relation to the housing in the course ofits opening and closing, it is feasible to provide sealing gasketsbetween the shell cover and the housing to protect the shell from dustand moisture, in addition when necessary, to other means increasing theexplosion-proof protection. The wear of the coating of theexplosion-proof surfaces is practically reduced to nil in said lock.

In view of the fact that, when closing the cover, the shelves of theturnable levers run on the meeting cover and housing perpendicularly totheir inner edges, the maximum travel of the friction surfaces of thelevers in the course of closing and opening is equal to the width of theshelf mm.), i.e. some ten times less than in case of bayonet covers.Moreover, the clips do not experience the common lack of flatness of themeeting edges of the shell cover and housing.

Therefore, the mechanical wear of the present lock is practicallyreduced to nil (5,000 closings and openings of the levers result in 0.05mm. of wear).

The prolonged operation of the lock in electric apparatus may cause someincrease in the gap between the meeting edges of the cover and housingto values exceeding prescribed values due to the worn elements of thelock in a quick-opened cover, as well as due to some other elementsbecoming deformed as a result of explosions.

A local increase in the gap in the present lock can be prevented bysubstituting new turnable levers for the old ones.

The overhaul of the lock is also possible by replacing the levers at newplaces, Le. to areas which were not previously operational.

Iclaim:

1. A lock for a quick-opened cover of a housing in explosion-proof andpressure-resistant shells, comprising: clips constituted as pivotallevers and turnable by a common drive; axles mounting said levers on theshell, said axles being perpendicular to the plane of a window providedin the shell housing and closed by said cover; a groove provided on oneend of each of said levers to accommodate meeting edges of the cover andhousing, said groove defining shelves embracing said edges when thelevers turn about their axles of rotation.

